TR adds more immersion to the Orthodox nations, plus more bonuses to the Russian region (Novgorod, Muscovy . . .) For the religion - as you might know, each Orthodox church is independent from one another, so they all have their own Patriarch (Except the Constantinople one who is an imperialist and meddles in foreign affairs). They add more religious authority.. which in its own gives more bonuses. Literally nearly every single thing this DLC adds works like this. Next thing is Iconography - You click on an icon and it gives you certain bonuses, so you pick whatever fits you or what you need the most. As for Russia - It's easier to colonize Siberia, there are new government types and a new unit. It doesn't add much and it's not fair to demand 10 euros, so just pick it up on a sale when it's more than 20% off.

Europa Universalis IV: Third Rome is another expansion for Europa Universalis IV. So what changed? We have new graphical presentation of our units which I really like, apart from that there are some new fun stuff for Orthodoxy and a new government. I read some comments people complained about the price but for me it's bearable and should not discourage! Solid DLC.

I can understand the idea of immersion pack - small DLC, expanding one nation, religion or something else. The problem is that there is barely any content in it, there is new unit models for 12 nations and advisor portrait and some new artwork for Russia - and that's pretty much it. It doesn't change gameplay in any significant way or add anything worth the price. Overall, not bad of a DLC, but it is aimed towards Russia enthusiasts rather than expanding the game itself. Grab it when on sale.

The Third Rome add on, called the first immersion pack, gives you more options for Russia and similar states. Some new adviser portraits are added and you gain new Russian based abilities with new units and government policies. Forming the nation of Russia gives you new government options allowing you to claim larger areas instead of single provinces. It does fit the name in adding a more immersive experience when it comes to playing as a nation in the Russian region but it with all the other DLC this is definitely not a necessary pick up. If you love the game and have been getting everything or really want to play as one of the effected nations this can interest you though the price can be a bit high for what you get.

This first expansion for Europa Universalis IV is a good one, giving you the opportunity to delve into the Russian Empire and experience its military and politics firsthand. This expansion is deep, and tasks range from colonizing the frontier to building up a fearless military, all in the hope of you becoming the Tsar that you want to be. This is a very well-put-together DLC and, if you loved playing Europa Universalis IV, then Third Rome is just for you.